The two glaciers around the Beerenberg volcano after the rock avalanche: Triggered by a 6.5-magnitude earthquake, large quantities of volcanic and permafrost debris tumbled down at the Kjerulf Glacier, spreading the material across the surface and covering the ice right up to the coast (left side of the picture). Credit: Grace Angelo
Permafrost refers to permanently frozen ground. The rock is held together by ice, much like cement binds concrete. However, when the ice thaws, the ground becomes weak and unstable. During an earthquake, this can trigger a series of natural hazards. An international research team investigated precisely such an event.
On March 10, 2025, an earthquake measuring 6.5 on the moment magnitude scale shook Jan Mayen island, triggering a rock avalanche that covered part of a glacier with rock and debris mounds known as molards, located approximately 7 kilometers (4 miles) from the epicenter.
The researchers set out to understand why this particular earthquake caused such pronounced slope instability, even though the region has long been seismically active. Was there an additional factor that made the rock especially vulnerable? And what role does ongoing climate change play? Their findings are published in Proceedings of the National Academy of Sciences.
